Southtowns27,

The below 1st screen shot shows the brake cylinder/hydraulic line circuits and corresponding connections taken from the 1967 Chevrolet Truck Engineering Book. Couldn't locate a 1968 version of the book, but a check of the May 1979 Chevrolet Master Parts Catalog (see 2nd screenshot) shows the same master cylinder was used for C10's from 1967-70.

The connection diagram would be the same for your '68 master cylinder as it is the same part for those year applications.

I would note that your '68 master cylinder was originally installed with a warning light switch assembly for the '67-'70 model years. That switch may or may not be needed for your '65 application. Hopefully someone else will chime in with more details or experience/knowledge.

Hope this info is helpful.

Dan

EDIT NOTE: I have submitted a flag to relocate this thread to either the Driveline or 60-66 Trucks forums as it doesn't fit into this forum.
Attachments
Dual reservoir master cylinder and brake line diagram 1967-Chevrolet-Truck-Engineering.pdf.png (733.28 KB, 62 downloads)
Master cylinder line connection diagram
1967 - 70 Master Cylinder data GMPartsWiki - Chassis and Body Parts Catalog P&A 72TL May 1979.png (434.7 KB, 62 downloads)
Master cylinder application data

Last edited by Gdads51; 04/13/2023 10:10 PM. Reason: Edited to correct info about brake switch
~ Dan
1951 Chevy 3 window 3100
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